Grade 6 - Mathematics9.35 Measuring an Angle with a Protractor - I

You can write the statement in two ways:
words: The measure of ÐABC is 320
symbols: mÐABC = 320

A protractor has an inner and outer scale. When you measure an angle, check to see which scale to use.

Procedure:

Place the protractor on ÐAOB such that the center of the semicircle (special mark on the protractor) coincides with ‘0’, the vertex of the angle and the diameter of the semi-circle (zero-zero line) falls on ray OA. Note that ray OA passes through the zero mark on the protractor.

Note the mark on the protractor through which ray OB passes. The number against the mark through which ray OB passes gives the measure of the angle.

In the above example the measure of ÐAOB is mÐAOB is 34 degrees and is written as: mÐAOB = 340Directions: Answer the following questions. Also write at least of your own showing angle and its measure using a protractor..